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High Frequency Oscillation hurt resistors in Magico A5 crossovers

Hi,I am looking for help understanding how HFO could blow crossover resistors in Magico A5 speakers. Equipment playing at the time of the incident is as follows...
Magico A5 speakersHegel H30 mono blocksHegel P30 preamp (lt and rt inputs on the Aux inputs from the laptop and Dragonfly Cobalt)
Dell laptopAudioquest Dragonfly CobaltAmazon Hi-res streaming
I was listening to Amazon music at a very moderate level when the application said there was an update available.I instinctively clicked accept while music was paying. It was only off for a few seconds to update and when complete and I restarted music the A5 tweeters were not on. These happened simultaneously and there was no audible noise what so ever indicating a potential issue. After multiple source tests and tweeter test, I was certain the tweeters were fine and it was an electronic issue. The cross overs were removed and sent to Magico and that was when I was told that HFO blew the resistors.
Can anyone explain how/why this happened so I can ideally avoid it happening again?
Thank you!
128x128howaanders8
fuzztone's avatar
fuzztone
5,496 posts
 
Begs the question: How did Magico explain it?
Resistors are rated for power applied not freak "update" events. 
howaanders8's avatar
howaanders8 OP
17 posts
 
"Resistors blown from high frequency oscillation" is all I got. Suggested that I have Hegel tested till I reminded them it was mono blocks and it happened simultaneously to both speakers. This stuff is way over my head.
jetter
2,951 posts
 
The trite explanation you received sounds like it was from a low tier employee.  You should request that an explanation be provided by someone in a position of responsibility who can explain or at least try to explain what has caused their product to stop working.

Are they fixing it under warranty?  

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